WHEN Catherine Cooper's son began suffering from persistent stomach aches, she discovered a very surprising cause

The first time I received a call to pick up my 11-year-old son Toby from school because he'd been sick I assumed he had a stomach bug.

But when it started to become a weekly occurrence, along with stomach pain, dizziness and such extreme lethargy that he would spend the day in bed, I started to become seriously worried.

Prior to this Toby had been a very healthy and active child who rarely saw the GP except for routine visits and suddenly we were there almost every week. The GP took my worries seriously and over several months Toby had a series of blood tests, stool tests, even an MRI brain scan, all of which showed up nothing unusual.

We'd go weeks without problems but then the same symptoms would return. I took him back to the doctor who referred us for an appointment with a paediatrician. He diagnosed abdominal migraine, a childhood form of migraine headaches.

Since Toby's diagnosis he has been able to better understand his condition [CATHERINE COOPER]

We'd go weeks without problems but then the same symptoms would return

"Abdominal migraine is a migraine equivalent," explains Dr Andrew Dowson, director of Headache Services at King's College Hospital, London and chairman of the Medical Advisory Board of Migraine Action.

"Around eight per cent of the school population suffers from some kind of migraine equivalent. Abdominal pain is by far the most common while others include dizziness, cyclical vomiting and bad growing pains."

Abdominal migraine tends to have the same triggers as conventional migraine: stress, changes in the weather, not eating regularly or dehydration; and responds to the same kind of drugs.

Most migraine equivalent sufferers will experience migraine later in life to a greater or lesser degree, says Dr Dowson, and the condition often runs in families.

There is currently no cure but there are drugs that can help with more severe symptoms. These tend to work well for children and cause fewer side effects.

Since Toby's diagnosis we have encouraged him to drink more water during the day and he has been prescribed an anti-nausea drug to take when he feels symptoms coming on. So far this seems to have helped.

Joanna Hamilton-Colclough, director of Migraine Action, adds: "It is easy for abdominal migraine to be mistaken for recurrent tummy bugs or even bad behaviour. We often speak to distressed parents whose children have suffered unnecessarily.

"If your child suffers from recurrent abdominal pain which may be associated with other symptoms but is well between attacks, it could be abdominal migraine and you should discuss this with your GP."

For more information on coping with migraine visit migraine.org.uk or call Migraine Action's helpline on 0116 275 8317